Add 'Customer Flag Updated' or 'Discussion Thread Updated' field to Projects/Project Tickets View Editor

Could you please Add 'Customer Flag Updated' or 'Discussion Thread Updated' field to Projects/ Project Tickets View Editor. Currently there is no way to select that option for the views and there is very little visibility for the projects tickets that have been updated by the client. 

Project tickets view below:

Same view but for service tickets does have this option to select:

Strangely same field under service tickets is called 'Customer Flag Updated' and for Project Tickets 'Discussion Thread' however there is no way to set up a view or a workflow rule around it. 

Thanks